Apparatus and method for selective crop harvesting

ABSTRACT

The apparatus for harvesting crops, particularly seed crops, comprises a mobile support structure (20) and a crop stripping device in the form of a rotor (30), which may be attached to height adjustable arms and is driven by drive means (22). The rotor (30) carries transverse rows of wedge form crop stripping elements (10) which may be combined with transverse ribs. The crop stripping elements having prominent leading edges, for example each formed at the junction between two faces which are acutely inclined with respect to each other. They may be attached to removable, raised, hollow mounting bars. The drive to the rotor may be so arranged that during forward movement of the apparatus the crop engaging elements (32) are propelled progressively through the crop, moving upwards at a front region. Seeds and other plant parts detached by the action of the rotor are impelled into a crop flow passage (27) under a crop guide cover (21). Essential dimensions of the rotor and crop engaging elements may be varied conveniently.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to apparatus for, and a method of,harvesting crops. It is concerned with detaching from plants, withoutcutting them, seeds, seed-bearing parts, seed bodies, and certain fruitsand/or foliage, collecting the detached material and separating from itthe wanted plant parts. The invention has particular application in theharvesting of grain crops, such as wheat, barley, oats and rice, butalso has application in the harvesting of other combinable crops likepulses, oilseeds and herbage seeds.

The invention has further application in the harvesting of nuts andother seed bodies and of flower heads, some fruiting bodies and foliage.

2. The Prior Art

Commonly the harvesting of seed crops, particularly cereal and herbageseed crops, is carried out by a once-over, destructive operation whichinvolves the cutting of the seed-bearing stems near their base.Harvesting machines, particularly combine-harvesters, are easilyoverloaded by large volumes of crop bulk, because these create problemsof seed detachment and separation.

The in-situ stripping of seeds from the uncut crop has been attemptedrepeatedly and has met with varying degrees of success. In-situ seedstripping by a rotary device became known through U.S. Pat. No.1,290,484 entitled `Standing Grain Harvester`. However, none of theearly diclosures made adequate provision for satisfactorily harvestingseeds or other wanted parts from crops which are unfavourably presented,because they are either severely leaning, tangled, twisted or laid, withthe wanted parts in close proximity to the ground or embedded in mattedcrop layers.

More recent proposals relating to in-situ seed stripping appear inpublished International Patent Applications PCT/W086/01972,PCT/W088/04885, PCT/W088/05626, and in GB 2188822A, all of which havethe same inventor as the present application. These more recentproposals disclose crop engaging elements which are preferablyresiliently mounted or made of resilient material, so that damage isavoided if inadvertent contact is made with the ground or with foreignobjects among the crop.

SUMMARY OF THE INVENTION

It is among the objects of the present invention to provide improvedapparatus for, and methods of, removing wanted plant parts from an uncutcrop, and to overcome many of the known disadvantages of existingharvesting machinery and methods.

More particularly, it is an object of the present invention to reducelosses of wanted plant parts, particularly seeds, which can occur insome crops and conditions with existing crop engaging elements, to keepthe fan effect and the energy requirement of crop stripping rotors low,to adapt stripping rotors quickly and easily to crops of differentphysical characteristics, dimensions and growth habits, to minimise thedetachment of unwanted material and to maximise the detachment ofindividual seeds, as opposed to whole or part seed heads, or of otherwanted parts, so that any subsequent task of separating and cleaning thewanted fraction or fractions is facilitated and the required mechanismsmay be kept small and simple.

According to one aspect of the present invention there is providedapparatus for harvesting crops comprising: a mobile support structurefor movement over the ground; moveable support means capable of beingdriven relative to the support structure and extending transverselyacross the direction of forward movement of the apparatus; a pluralityof crop engaging elements cantilevered outwards from the moveablesupport means; means for driving the moveable support means so that thecrop engaging elements comb through the uncut crop at a front region, toaccess, detach and impel wanted parts including seeds; crop containmentand guide means extending over or under the apparatus to preventdetached crop particles becoming lost and to direct them rearwards forcollection; characterised in that at least some of the crop engagingelements comprise crop stripping elements, each forming at least in theouter region a wedge effective in the direction of rotation, forpenetrating and parting the undisturbed crop mass, and each having, fordetaching and laterally impelling wanted plant parts, reclined sidesurfaces with outer boundaries shaped to promote smooth sliding andfunnelling of crop material into principal inwardly andcircumferentially extending crop engagement channels formed betweenlaterally and circumferentially adjacent elements.

It is believed that separation from the crop mass of the wanted parts,such as seeds, is achieved in embodiments of the invention primarily bybeating, prising and shaking such wanted parts off the crop. Othermechanisms involved include bending, breaking, cleaving, tearing andrubbing.

According to another aspect of the invention, there is provided a methodof harvesting a crop comprising: moving through the uncut crop anapparatus according to said one aspect of the invention whilst drivingsaid moveable support means so that the crop engaging elements combthrough the uncut crop at a front region of the apparatus, whereby eachof said crop stripping elements forms at least in the outer regionthereof an acute wedge effective in the direction of rotation and whichparts the undisturbed crop mass, to access and detach wanted parts fromthe crop by the effects of reclined surfaces, with outer boundariesshaped to promote smooth sliding and funnelling of the plants intoprincipal inwardly and circumferentially extending crop engagementchannels formed between laterally and circumferentially adjacentelements, the method including impelling the detached crop parts inlateral directions towards a collection facility.

The apparatus of the invention operates by detaching from the seed-,flower- or fruit-bearing stems of uncut plants the wanted parts bycombing through the crop, leaving the stems standing.

The apparatus preferably also comprises associated compact apparatus forseparating already threshed seeds from the wanted and unwanted materialdetached by combing, and for completing the detachment and separation ofseeds from whole or part seed-bearing heads broken off and collectedduring the combing process.

The present invention finds application in self-propelled machines forharvesting seed and forage crops, and in machines which are mounted onsingle- or multi-axle tractors to be pushed or pulled through the crop.

The form of the crop engaging elements has beneficial effects upon theeffective operation of preferred embodiments of the invention. The sizeand shape of the elements, together with their operating angles andlateral and circumferential spacings, may be selected to maximise thedesired effects in terms of seed detachment and recovery during thecombing process.

As plant stems are stroked by fast moving crop engaging elements, thestems are deflected more readily laterally than the relatively heavyseed-bearing heads. Because of their inertia, the seed heads adjacent toelements can be subjected to a whiplash effect. This causes seeds to beshed, particularly when seed heads collide with the crop facing regionsof the elements or with each other. Sometimes all or part of a headstill containing seeds can break off.

Individual seeds which become detached on, or collide with, cropengaging elements bounce off and, in operation of known harvesters, maybe launched into trajectories, particularly forwardly directedtrajectories, which are unfavourable for recovery.

In accordance with one preferred feature, in embodiments of theinvention, the outwardly projecting crop combing elements are formedfrom resilient material and are smoothly shaped to promote unimpededsliding of crop into the principal stripping regions and to minimise thedetachment of unwanted plant parts by tearing.

The elements may take the general form of single-bevel and double-bevelwedges, to provide at their side surfaces incident angles with the cropsuch that detached crop parts, especially seeds, are directed intoinitial trajectories which are directed sideways and in the direction ofrotation. It is preferred that any outer boundaries are inwardly curved,at least in the region of transition into the trailing boundaries of theside surfaces, to avoid in some crops and conditions plant stems gettingcaught and being torn by abrupt inflections of boundaries.

Conveniently the elements may comprise an outer wedge-shaped shoe orhead for prising the crop mass apart and a narrower stem section whichis secured at its inner end to the moveable support means. In theoutward direction the stem may be flared or tapered from its smallestcross-section to meet the boundaries of the crop dividing shoe.Optionally the stem may also be flared or tapered inwardly from itssmallest cross-section.

During movement through the crop whilst this is unsupported by any othercomponent of the apparatus, lateral displacement of plant matter isgreatest at the bottom-dead-centre position of rotation, when thetransverse plane of the shoe lies normal to the general orientation ofplant stems, and it is least at the front-dead-centre position ofrotation when the stems lie generally parallel with the transverse planeof the shoe.

In the outward direction the elements may be plain, or they may beribbed, corrugated or otherwise profiled to reduce mass and friction andto guide detached crop particles into favourable paths and trajectoriesfor recovery. Cavities may be provided in the stem and head sections tomaximise the yielding ability of the elements, including in the inwarddirection. To prevent undesirable elongation under centrifugal effect,elements of great flexibility, particularly hollow elements, may haveincorporated into their walls outwardly oriented fibres of appropriatetensile strength so that they do not interfere with the yeildingcharacteristics of the elements in response to overloads or contact withforeign objects in the crop.

The cross-sectional dimensions of stems may be chosen to promotepreferential yielding laterally or fore-and-aft. Relative to atransverse radial plane passing through the base of the stems, theelements may be symmetrical, i.e. equally effective in either directionof rotation, or asymmetrical; when seen in side elevation in thetop-dead-centre position of a stripping device rotating clockwise,elements with outer opening shoe may take the general shape of a `T`,and `I` or an inverted `L`. The boundary regions of the shoe may berounded, tapered or otherwise smoothed in the outward direction, toprevent chafing or cutting of the crop.

Crop engaging elements with outer opening shoe and reduced stem sectionare particularly suited to operating in the overshot mode, so that theymove upwards at a front region, and they are particularly effective inlifting severely laid crops for efficient recovery of wanted plantparts. The flared or tapered transition region from the stem to theouter shoe portions assists in guiding detached crop particles intolaterally and upwardly directed paths.

In accordance with another preferred feature the crop stripping elementsmay comprise fins, each forming or being provided with a prominentleading edge region for entering into the crop with minimal disturbance.The prominent leading edge of the crop stripping elements may extendoutwards in one direction or in more than one direction, and it mayextend in a straight or undulating line.

Conveniently the elements may be flat in their attachment region forpredictable yielding in that region if an impact with the ground or witha heavy object should occur. The flat attachment region may be laterallyangled relative to the transverse rotor axis so that yielding of theouter region of an element into a reclined position may take place in aninward and lateral direction.

Conveniently there may extend from the prominent leading edge of a cropstripping element on one or both sides a laterally reclined surface sothat in operation of the elements the previously undisturbed crop massis prised apart by the action of a single- or double-bevel wedgerespectively, and wanted plant parts are beaten or shaken off and areimpelled laterally and at the same time in the direction of rotation ofthe elements. The trailing side surfaces may be flat, curved, grooved,ribbed or otherwise contoured.

In some embodiments the trailing boundary region of each reclined cropengaging surface may be generally parallel with the prominent leadingedge. Preferably the outer boundary may be curved to lead smoothly intothe trailing boundary. Other element-defining boundaries may bestraight, curved, serrated, scalloped or otherwise profiled to achievethe desired effects.

Conveniently there may be provided, preferably in the boundary regionsof the crop stripping elements, recesses and/or protrusions to enhancethe stripping effect and impel detached particles into laterally and/orinwardly directed safe recovery trajectories.

Conveniently circumferentially adjacent crop stripping elements may beso spaced laterally that their reclined side surfaces overlap in thedirection of movement of the elements, or there may be provided lateralclearance.

In accordance with a further preferred feature a compound crop strippingelement may comprise a projection in the form of a strong spineextending outwardly and providing a prominent leading edge. The trailingregion of each laterally reclined crop engaging surface may comprise aflap formed of thinner and more flexible material, to allow preferentialyielding of the side regions in response to increasing crop pressure andfriction.

The flexible side regions may be divided by lateral slits, preferablynormal to the prominent leading edge, so that each section forms a flapwhich may yield independently, allowing intrusion of stiff plant stemsinto the normal profile of the elements, so that the stems aremomentarily enveloped from the sides.

To facilitate the repair of damage or wear to thin flaps and to adaptthe elements readily to different crops and conditions, each element mayhave a spine comprising a leading and a separate trailing portionbetween which a shaped insert of thin flexible sheet-like material maybe clamped in position. The inserts may have different shapes anddimensions, depending on the effects to be achieved.

In accordance with a yet further feature the crop stripping elements mayresemble perpendicular or oblique cones or cylinders. In the cropengaging side regions elements of such general shapes afford completeabsence of abruptly ending surfaces and outwardly extending abrupt edgesformed between faces substantially normal to each other. In consequencecones and cylinders, which may be hollow or solid and alternativelytruncated, avoid the harsh scraping effects of abrupt side edges andusually lead to only small amounts of unwanted material and unthreshedseed heads being torn off. Additionally, compared with flat planarelements of triangular shape which can cause high losses in some fieldconditions, they impel the detached crop particles mainly laterally andin the direction of rotation for safe recovery.

A further advantage is that such elements may be mounted so that theiroutwardly extending axis is forwardly inclined by up to 45°, or more forspecial purposes; this can greatly assist in the harvesting ofdifficult, particularly strong-stemmed crops, which are lying away fromthe rotor in the direction of forward movement. Preferably the effectivelength of conical and cylindrical elements is not more than 6 times, andmost preferably 2 to 3 times, the maximum diameter.

In embodiments of the invention the laterally reclined crop engagingsurfaces of wedge-form elements may lie in more than one plane, andthere may be provided surface contouring, including concave or convexmoulding and transverse or longitudinal ribbing or corrugating, toimprove the stripping and impelling characteristics of the crop engagingsurfaces and boundary regions and of any recesses and protrusions.

In preferred embodiments of the present invention the crop strippingelements may form separate or integral extensions of transversely orhelically arranged and outwardly directed flat or corrugated ribs. Theribs may be provided with serrations at their outer edge, so thatbroken-off crop fragments still containing seeds are subjected to a moresevere threshing effect on impact with the edge than would be providedin the absence of an edge or by a straight, smooth edge.

Conveniently crop stripping elements may be attached also to themoveable support means so that the elements are interspersed with thetransversely or helically arranged ribs. Detached crop parts which fallor slide into the space swept by the ribs may be impelled outwards forrecovery. The ridges and depressions formed in corrugated ribs areadvantageous, particularly in the harvesting of small and light seeds,in that detached seeds may be collected together into distinct streams.

Conveniently the side edges of acutely serrated and preferablycorrugated ribs may co-operate with the stripping elements to directcrop stems laterally into the zone of influence of the elements.Circumferentially successive, acutely serrated ribs may be staggeredlaterally relative to stripping elements, to intercept and re-direct alldetached crop parts.

Conveniently crop stripping elements which form extensions oftransversely or helically arranged ribs may be connected with the ribsin continuation of the principal plane of the rib in the attachmentregion, or in a plane different from the plane of the rib in theconnecting region.

As an alternative to attaching the crop engaging elements totransversely or helically arranged flat or corrugated ribs or directlyto the moveable support means, which may be tubular of circular orpolygonal cross-section or may consist of a continuous belt, individualelements, or continuous arrays of elements, may be attached by bondingor by fasteners extending axially, tangentially or in intermediatedirections to transverse mounting members. Such members may be hollowand may comprise, for example, lengths of appropriately shaped channelsection, bar, rails or batten material made from metallic ornon-metallic substances.

Conveniently the intermediate mounting means may be provided at theinner end with flanges extending in and against the direction ofrotation of the crop engaging elements. Intermittent or continuoustransverse guides, secured circumferentially spaced to the moveablesupport means, may be provided to allow sections of the intermediatemounting means carrying arrays of crop stripping elements to be slidinto position or removed from the side. Conveniently, retention of theend sections may be by set bolts or other known locking means.

Alternatively the intermediate mounting means may be provided at thebase with recessed studs, which register for insertion with slottedholes cut into the surface of the moveable support means. Afterinsertion of the recessed studs into the holes, lateral sliding of thebars in the direction of the slots locks the bars in position.

In cross-section the mounting members may form symmetrical orasymmetrical mounting pedestals which may have steep or slanting sides.Conveniently the crop-facing surface or surfaces of the members mayserve to impel detached crop material in the direction of rotation ofthe crop engaging elements. Conveniently also the outer surface andedges of the bars may combine with the elements to locate the elementsin their intended positions and to promote stripping of wanted plantparts. To facilitate such effects, outer surface and boundary regionsmay be profiled or contoured, for example they may be provided withrecesses and/or protrusions.

Axial fastening of crop engaging elements to transverse mountingmembers, which may be hollow or be made conveniently of wood orsynthetic materials, may be facilitated if threaded nuts or inwardlyextending screws, bolts or pins are moulded into the base portions ofelements. Alternatively there may be provided flanges or webs extendingto one or both sides of the transverse centre line of arrays of joinedcrop engaging elements, to enable fastening by any convenient means.

The method of attaching crop engaging and crop stripping elements tomounting bars, which are then slideably or otherwise rapidly secured asassemblies to the moveable support means, provides several advantages.The most important of these include the ability to repair and replacefaulty elements quickly and easily, to interchage types of elementsreadily, for example to adapt the apparatus for harvesting differentcrops, and to vary the effective stripping rotor diameter and/or thenumber of transverse rows of elements for specific purposes.Conveniently, alternative mounting bars may have differentcross-sectional shapes and dimensions.

To facilitate removal and replacement of quick-fit mounting bars,particularly slideably located bars, a suitably dimensioned andpositioned aperture in one or both side plates of the rotor housing maybe provided. Alternatively, provision may be made for the guide or otherretaining means of one mounting section in each transverse array ofelements to be removed or rendered inoperative.

Conveniently some forms of discrete crop stripping element may bemounted so that in operation each such element is self-rotating aboutits outwardly extending axis. Rotation can enhance the stripping effect,contribute to smooth crop flow, minimise the detachment of unwantedparts and help to distribute wear evenly.

In embodiments of the invention the height-adjustable moveable supportmeans to which the crop engaging elements are secured may be driven tomove the elements through the crop in the overshot or the undershotmode, that is to say in such a way that the elements move respectivelyupwards or downwards at a front region. Conveniently the crop flowpassage may extend around the upper part of the crop stripping device,when the device is driven in the overshot mode. In the outward directionthe passage may be defined by a preferably smoothly curved crop guidecover which serves to direct detached plant parts rearwards for furtherprocessing, cleaning and collection.

In some embodiments of the invention the crop stripping device may bedriven so that the crop engaging elements move downwards at a frontregion. This form of operation is particularly appropriate in shortcrops and when the crop stripping elements are formed to impel detachedplant parts initially inwards relative to the tips of the elements.Conveniently the crop flow passage then extends around a lower part ofthe crop stripping device, and it may be defined in the outwarddirection by one or more conveying rotors, or preferably by a beltconveyor, which may be cleated or provided with transverse slats inorder to ensure efficient collection of detached particles at a lowlevel.

Preferably the lower conveying means are provided with means foradjustment of the position and angle of inclination relative to theground, independent of the height adjustment of the stripping rotor andof the apparatus as a whole. Preferably also the stripping rotor isprovided with means for adjustment of its fore-and-aft position, so thatfrom a wide range of possible settings the most appropriate combinationmay be selected for effective and efficient crop recovery regardless ofthe conditions of the crop and of the ground.

The height-adjustable moveable support means may comprise a horizontalrotor mounted in the mobile support structure substantially transverseto the path of forward movement of the apparatus, or leading at oneside, the rotor being provided with at least two transversely arrangedarrays or one helically arranged array of crop stripping elements.

Alternatively the height-adjustable, driven moveable support means maycomprise a continuous belt or flexible sheet which extends across thefull working width of the apparatus, generally transversely to its pathof forward movement and horizontally, vertically, or at the topforwardly inclined. The full-width belt or other means may be supported,under sufficient tension to transmit the required driving force, betweentwo rollers or sets of sprockets or wheels.

In embodiments of the invention there may be combined, with the cropstripping device, preferably transversely oriented apparatus forapplying primary separation and cleaning to the stripped off seed beforedelivering it for final separation, cleaning and collection.Conveniently, one form of primary separation and cleaning may beincorporated within the crop guide cover. By relieving the curvature ofthe cover, the relatively heavy seeds may be allowed to continue to flowat a high level towards a collecting auger, whilst and air curtaindirected downwards from a plenum through a recessed slot deflectsmaterial on to the ground through a gap behind the stripping rotor.

Additional primary cleaning apparatus for stripped seed samplescontaminated with coarse unwanted crop fractions may be provided byreplacing with a perforated screen or sieve the floor plate of the kindof crop elevator which is commonly used in conventional combineharvesters for feeding the cut material from the cutting table to thethreshing mechanism. Cut seed-bearing crops do not contain worthwhilequantities of free seeds, but during in-situ stripping, particularly ofgrain crops, over 90% of the seeds may be threshed by the strippingdevice of the present invention.

The screen which may be provided under the crop elevator may have fixedapertures of different shape and size, or it may be anadjustable-aperture or special sieve. The screen may be kept static, orit may be reciprocated in or across the direction of crop flow or abouta pivot positioned in any of a range of locations in or adjacent thescreen area.

The present invention may be put into effect in such a way that theapparatus may be attached to and driven by a tractor of single- ormilti-axle configuration, that it may be mounted on a self-propelledvehicle with appropriate controls and optionally provided with finalseed cleaning means and a holding tank with emptying facility, that itmay replace the cutting tables of conventional combine harvesters, thatit may be combined with apparatus for compacting the incidentallydetached material-other-than-seed (hereafter referred to as MOS) and/orthe crop residue, or that it may replace the cutting or pick-up heads offorage harvesters. The last-mentioned application provides theadvantages that the comminution mechanism of the forage harvester actsas an effective threshing mechanism to dislodge any seeds not separatedfrom the stripped-off seed heads and that it chops any detached longmaterial, thus increasing the load density in any collecting tank.

Generally the invention finds application in the harvesting of matureseeds by a single pass or in successive passes, including cereals,pulses, oil seeds and herbage seeds, and in the harvesting of whole seedbodies, some fruiting bodies and foliage fractions.

Preferred embodiments of the present invention to be described provide,in addition to compactness of construction offering low weight and cost,the advantages of high work rates and hence low harvesting costs,timeliness of harvesting, extended time available to the farmer forpreparing a seedbed for the next crop, and sufficient and economicaldisposal or utilisation of the crop residue, which dries quickly afterrain and is favourably presented for burning, chopping or harvesting, asrequired.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described by way of examplewith reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic cross-sectional side elevation of a stripperharvester embodying the invention;

FIGS. 2a, 2b and 2c are respectively front elevation, side elevation andplan view of a crop stripping element having a crop dividing shoe at itsouter end;

FIGS. 3a, 3b and 3c are respectively front elevation, side elevation andcross-sectional view in the direction of arrows AA in FIG. 3b of analternative element to that shown in FIGS. 2a-c;

FIGS. 4a, 4b and 4c are respectively side elevation, front elevation andplan view of an alternative element to that shown in FIGS. 2a-3c;

FIGS. 5a and 5b are respectively side and front elevations of analternative element to that shown in FIGS. 4a-c;

FIGS. 6a, 6b, 7 and 8 show perspective diagrammatic views from arearward direction of three different configurations of crop strippingelement on entering a cereal crop;

FIG. 9 indicates schematically the interaction between crop stems, seedheads and wedge-form stripping elements with crop-parting outer shoeportions, as it appears in plan view in a section of the development ofthe surface of a crop stripping device;

FIGS. 10a-c, 11a-c and 12a-c are schematic representations of theprincipal forms of crop stripping element having a crop-parting shoe inthe outer region;

FIGS. 13a, 13b, 13c and 13d are respectively cross-sectional elevationfrom one side, front elevation, cross-sectional elevation from the otherside and plan view of asymmetric wedge-form crop stripping elementsincorporated into corrugated transverse ribs provided at the base withflanges or webs for axial fastening;

FIG. 14 shows symmetrical alternative elements to those in FIGS. 13a-d;

FIGS. 15a and 15b show respectively front and cross-sectional endelevations of compound crop stripping elements having replaceableflexible side flaps;

FIGS. 15c-e show replaceable inserts providing side flaps of alternativeshapes;

FIGS. 16a, 16b and 16c are respectively front elevation, side elevation,partly in section, and plan view of fin-like crop stripping elements;

FIGS. 17a and 17b are respectively front elevation and plan view of anarrangement of cone-shaped crop stripping elements, mounted indirectlyon the moveable support means in different orientations;

FIGS. 17c and 17d are side elevations, partly in section, of cone-shapedcrop stripping elements mounted indirectly on the moveable support meansin different orientations;

FIGS. 18a, 18b and 18c are respectively front elevation, partly insection, plan view and side elevation, partly in section, of alternativecrop stripping elements to those shown in FIGS. 17a-d;

FIGS. 19 to 23 are side elevations and plan views of alternative formsof discrete crop stripping element;

FIG. 24 is a perspective front elevation of a crop stripping rotor andits crop containment/guide cover embodying the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Throughout this specification corresponding components of the variousarrangements have been given identical reference numerals. For brevityand simplicity the functions and inter-relationships between the variouscomponents are described and explained only when they are firstmentioned and not fully in connection with each figure. Thus it is to beappreciated that each time corresponding components with identicalreference numerals are shown or referred to, the appropriate descriptionapplies.

Referring first to FIG. 1, there is shown in diagrammaticcross-sectional side elevation a generalised layout of one embodiment ofthe present invention for harvesting crops by stripping off the wantedparts in situ. The apparatus comprises a mobile support structure, orframe, indicated generally at 20, for movement over the ground whenpushed or pulled by a tractor or when attached to a self-propelled powerunit.

Connected to frame 20 is a moveable support means 32; in the embodimentshown this is a hollow tube, but other support means may be used, forexample a continuous belt. Mounted on the support means 32 is aplurality of outwardly projecting crop engaging elements 1, which maytake several different forms, as described hereinbefore and hereafter.In combination the moveable support means 32 and the crop engagingelements 1 form a rotary crop stripping device 30. This is driven bydrive means indicated diagrammatically at 22, which may comprise a drivetrain made up of gears, belts, chains and/or hydraulic means, usingpower derived conveniently from the engine of the operating unit.

The direction of rotation of crop stripping device 30 is such that thecrop engaging elements 1 comb through the previously undisturbed crop inthe upward direction at a front region, prising the unrestrained cropmass apart by a wedge action. Detachment and impelling for collection ofwanted plant parts is accomplished at peripheral speeds in theapproximate range of 8 to 40 m/s at the tips of elements 1 by beating,bending, cleaving, tearing and rubbing the crop. It is achieved to anextent also by shaking due to the whiplash effect resulting fromappropriate lateral inclinations and the lateral and circumferentialspacings of the elements as they comb through the crop.

In operation of the device there are formed between laterally andcircumferentially adjacent crop stripping elements 1 inwardly andcircumferentially extending crop engagement channels bounded by thereclined outer and/or side regions of adjacent elements 1. These cropengagement channels may also be described as the crop stripping regionsof rotor 30.

To prevent material detached from the crop by stripping device 30becoming lost, there is provided a crop containment and guide cover 21;this cover is preferably smoothly curved and extends from in front ofthe seed stripping region to beyond the rear of stripping device 30. Theunobstructed space beneath the cover 21 forms a crop flow passage 27.

In the embodiment shown in FIG. 1 the stripped material is propelledtowards an adjustable transverse aperture 81 through which an aircurtain from a plenum or manifold 80 may be directed downwards at a gapbetween the rotor 30 and the crop collecting auger 83. The plenum 80 maybe supplied with air from a remote fan or fans. When the apparatus isused to harvest seeds and other bodies which are denser thanincidentally removed foliage particles, the densest fraction tends tomove in the upper region under the crop containment cover 21.

The air curtain may be adjusted to allow the wanted dense fraction topass readily, to be collected in upper auger 82 for conveying to oneside of the apparatus and thence into a container. The somewhat lighterand larger fractions may be deflected by the air curtain into cropcollecting auger 83, whilst the lightest fractions may be blown on tothe ground through the gap in the apparatus behind rotor 30.

Auger 83 has series of retracting fingers over part of its length whichserve to push the collected material into ducting 84 where an elevator85 conveys it to a higher level for further processing or collection.Any seeds which may still be present may be separated from the coarsenon-seed fraction through a screen 86, which is shown diagrammaticallyto provide the floor of duct 84. The floor may be made rough optionallyby sieve protrusions, to provide resistance to the movement of cropparticles still containing unthreshed seeds, so that such seeds may bedislodged as they are forced over the protrusions by the crop engagingmembers of elevator 85. A ramp 87 directs the further separated seedsinto a transverse conveyor 88, conveniently an auger conveyor, fortransfer and subsequent collection on one side of the apparatus.

Screen 86 may be provided over the whole or part of its surface areawith apertures which allow mainly seeds and not coarse material to passthrough. The apertures may be of fixed size and shape; alternatively thescreen 86 may be a sieve with adjustable apertures, for example afrog-mouth or laminar-type sieve. Conveniently the screen 86 may beactuated by pivotal motion, or it may be reciprocated in or across thedirection of crop flow, or it may be kept static.

Reference is made next to the crop engaging elements which perform theimportant functions of opening up and dividing the undisturbed crop massand providing access to the wanted plant parts so that these may bedetached and impelled into safe paths for collection.

In FIGS. 2a, 2b and 2c there are shown respectively a front elevation, aside elevation and a plan view of a crop stripping element 1 comprisingan outer shoe or head 9 principally for parting the undisturbed crop anda stem portion 2 primarily for detaching and impelling wanted cropparts. From its narrowest region the stem portion 2 may be flared ortapered in the outward direction to meet the leading and trailingboundary regions of head portion 9.

Alternatively, in the outer region the sides of stem section 2 may beprovided with steps 19 and relief regions 16, as shown in brokenoutline, to assist in the removal of wanted plant parts, particularlyseeds, from the forward facing regions of plant stems.

Optionally stem portion 2 may be flared, tapered or stepped laterallyalso in the inward direction, to provide firm support in the mountingregion. Depending on the loads imposed in operation on the element,which is made preferably of impact and wear resistant flexible material,yielding may take place in the narrow stem region in any direction.

A cavity 35 extending centrally inwards for most of the way from theouter surface increases the yielding potential of the element, savesplastic material and permits insertion and access to axial fasteningdevice 36.

Preferably, element 1 is secured to the outer surface of channel-sectionmounting bar 33, which, at its base, has two flanges turned towards eachother in contact with the outer surface of moveable support means 32,the flanges being retained by guides 8 secured by screwing, pinning,welding, bonding or other methods to the moveable support means 32. Thearrangement allows lengths of mounting bar 33 complete with elements tobe withdrawn, for repair or substitution, through an aperture which maybe provided in one or both side plates of the rotor housing.

In optional arrangements, shown later in FIGS. 17 and 18, the baseflanges of mounting bar 33 may be turned away from each other toregister with separate guides 8 located alongside the channel section.Conveniently, as an alternative method of replacing elements or mountingbars, one of the guides 8 may be made detachable, to allow at least onesection of bar 33 to be removed initially; adjacent sections may then beslid along for subsequent removal.

Conveniently the outwardly extending sides of mounting bar 33 serve toimpel detached crop parts in the direction of rotation of theelements 1. Conveniently also the dimensions of mounting bar 33 may bevaried to suit different requirements. In particular, if the outwardlyextending height is varied, the effective diameter of stripping rotor 30may be changed, or it may be kept constant when elements of differentlength are to be used.

To prevent rotation of element 1 about its outwardly extending axis, theouter surface of mounting bar 33 may be recessed transversely, as shownin FIGS. 2a and 2b. Other profiles of the outer surface may be providedto facilitate the mounting of elements and assist in the detachment andrecovery of wanted crop parts. To permit tangential fastening ofindividual elements or of strips of conjoined multiple elements,mounting member 33 may be provided in its outer region with atransversely extending fin or flange.

FIGS. 3a, 3b and 3c show respectively a front elevation, a sideelevation and a cross-sectional view in the direction of arrows AA inFIG. 3b of an alternative element in which the flared stem section 2 isprovided with corrugations comprising outwardly extending recesses 16and ridges 17. One such ridge forms the prominent leading edge 4. Theouter boundary of opening shoe 9 is convex in the direction of rotation,and the shoe has a transversely V-form central recess with an innerboundary which is concave fore and aft.

A central cavity 35 extends inwards from the shoe portion for most ofthe length of the stem section. Conveniently the element may be made tobe a thick-walled hollow element, so that minimal material is requiredand rapid and responsive yielding may be provided in case of impact withforeign objects.

The wear qualities of some plastics, particularly polyurethane, improvewith decreasing hardness, but the risk of elongation under centrifugaleffect increases. Use of highly wear resistant materials may befacilitated by the incorporation during manufacture of bundles of fibresof high tensile strength, as are shown by way of example at 37 in FIG.3c.

FIGS. 4a, 4b and 4c show respectively a side elevation, a frontelevation and a plan view of an alternative element 1 with outer cropparting shoe 9, the element comprising essentially only the leading halfof the elements described in FIGS. 2 and 3. An optional featurecomprises rearwardly extending, flexible, curved wings 10, whichincrease the crop parting effect of shoe portion 9 and enhance theeffectiveness of stripping. Void space 35 is deepest in the trailingedge region of opening shoe 9.

In FIGS. 5a and 5b are shown respectively side and front elevations ofan alternative element to that shown in FIGS. 4a-c. The stem portion 4is coarsly corrugated or grooved. Additionally the tip of shoe portion 9lies outwardly displaced relative to the trailing boundary. This featurehelps to penetrate and recover severely matted crops.

In FIGS. 6a, 7 and 8 are shown perspective diagrammatic three-quarterrear views of three different configurations of crop stripping elementas they enter a cereal crop in which, as often happens in practice, someof the crop stems are bent over so that their seed heads are located ata low level.

The element in FIG. 6a has an outer crop parting shoe 9 and issymmetrical about its outwardly extending axis. In thebottom-dead-centre position, when the plane of the opening shoe isnormal to the general orientation of the crop stems, the stems areforced apart by at least the width dimension of the shoe. At thefront-dead-centre position, which is depicted in FIG. 6b, the plane ofthe shoe portion lies parallel to the crop stems, allowing them to closein and to make rubbing contact with the stem portion 2 of the element.During passage through the lower front quadrant of rotation, any seedsstripped off will be directed mainly laterally and upwardly by virtue ofthe shape of the outer region of the element.

Because of the inclination of the principal crop engaging side surfacerelative to the direction of movement of the single-bevel element withprominent leading edge 4, shown in FIG. 7, any seeds dislodged will beimpelled mainly laterally and also in upward directions.

For comparison a planar crop stripping element 1 with flat leadingsurface presented initially parallel and face-on to the crop stems isshown in FIG. 8. Such an element may launch particles easily dislodgedfrom mature seed heads in the lower crop regions into low trajectoriesunfavourable for safe recovery. The action of the abrupt edges issevere, so that in commercial seed crops substantial quantities of MOSmay be detached incidentally.

In FIG. 9 is indicated schematically the interaction between crop stems,seed heads and crop stripping elements having outer opening shoeportions 9 and reduced stem sections 2, as seen in plan view in asection of the development of a surface of a crop stripping deviceaccording to the invention. The staggered formation of the elements inand across the direction of movement relative to the `tethered` cropinduces lateral whiplash.This causes the heavy seed heads to be threshedby repeated impact, in the crop engagement channels, with the sideregions of laterally and circumferentially adjacent elements and witheach other. Detached particles, particularly seeds, are impelledsideways and in the general direction of rotation of the elements.

In FIGS. 1a-c, 11a-c and 12a-c are shown schematic representations ofthe principal forms of crop stripping element having a crop parting shoein the outer region and a reduced-section stem. The `a` column depictsside elevations, the `b` column corresponding front elevations and the`c` column front elevations of special front profiles for specific cropsand conditions.

Thus, FIG. 10 represents an element in which the stem section is reducedsubstantially in width but only marginally fore and aft. Consequently,yielding under excess load conditions can be expected to take placeprimarily to either side. The special front profile of the stem portion2 provides a central ridge 19 extending from front to rear. It allowsparticularly coarse-stemmed and bulky crops to be guided by theintermediate ridge 19 into inner and outer stripping spaces 16 forefficient removal of wanted parts.

The element represented by FIG. 11 has a stem portion 2 which issubstantially reduced in section fore and aft but only marginally acrossthe width. In consequence yielding of the outer shoe section may beexpected to take place primarily in the direction of rotation. Thespecial front profile in FIG. 11c is similar to that in FIG. 10c but isparticularly suitable for sparser and more vulnerable crops whichrequire less space and gentler treatment.

FIG. 12 represents an element in which the stem section 2 is dimensionedto yield readily in any direction. The special front profile, providingmultiple ridges 19 and furrows 16, is particularly suited tofine-stemmed crops and others which are difficult to strip.

For some crops and conditions it is preferred that the stem portions ofthe crop stripping elements referred to in FIGS. 1 to 6 and 9 to 12 havecrop engaging side and outwardly extending boundary regions formed inthe rearward direction of smooth continuous surfaces, free of abrupt anddefinitive edges or other disruptions and surface discontinuations, sothat plant parts are detached entirely by the effects of beating withoutscraping. Such action gives important benefits, compared with theeffects of elements provided with conspicuous side edges for actingaggressively upon the crop. In particular, detachment of MOS and of cropportions still containing seeds is usually substantially less, and theproportion of seeds threshed out of the seed heads cleanly can be higherby a factor of up to around 2, sometimes totalling over 98% of thecollected seed yield.

FIGS. 13b and 13d show respectively a front elevation and a plan view ofa section of a transverse, corrugated array of crop stripping elements 1in which the crop is prised apart by prominent leading edge 4. As seenin FIG. 13b, trailing edge 3 emanating from the outer end of prominentleading edge 4 is slanted sideways and converges on to trailing edge 3of the adjacent element 1, the outer edge 5 of which is curved, to helpfunnel crop smoothly for stripping into recess 16 between adjacentelements. In operation of the elements, trailing edges 3, on both sidesof the inner part of recess 16, appear substantially parallel.

FIGS. 13a and 13c are respectively views in the direction of arrows Aand B in FIG. 13d normal to the two side faces of each corrugatedelement 1. A particularly advantageous feature of this arrangement ofcorrugated crop stripping elements is the generously dimensioned outerinlet funnel, generally indicated at 16, which is formed between twosurfaces lying in different planes relative to one another.

Optionally the `lobes` of the elements depicted in FIGS. 13a-d may beconcave on their crop facing side, as indicated in the left-hand elementof FIGS. 13b and 13d, to favourably affect the trajectories of impelleddetached crop particles, particularly seeds.

FIG. 14 is a front elevation of a short section of an alternative arrayof corrugated crop stripping elements 1, the elements being symmetricaland having recesses 16 formed by trailing edges 3 in continuation ofcurved outer edges 5. The serrated corrugations 7 at the inner end ofrecesses 16 serve to divide the trapped crop and to guide it sidewaysfor complete stripping by trailing edges 3 and protrusions 19.

Elements which are corrugated or are attached to corrugated ribs may besecured by means of tangential fasteners to plain or shaped supportsextending outwards from the moveable support means, or they may besecured by axial fastening means on to the surface of the moveablesupport means or on to raised transverse members serving as mountingbars. Axial fastening of the elements shown in FIGS. 13 and 14 isfacilitated by the provision at their base of circumferentiallyextending flanges or webs 6 joined to the corrugations on one or bothsides. Webs 6 also ensure that the angular relationship of thecorrugated surfaces is maintained.

FIG. 15a is a front elevation of crop stripping elements 1 havingflexible side regions, and FIG. 15b is a cross-sectional end elevationof one such element when viewed in the direction of arrows CC in FIG.15a. Leading edges 4 are provided by spine-like projections extendingoutwardly from a common base flange 6 provided for attachment bygenerally tangential fastening means directly or indirectly to moveablesupport means. The laterally extending wings or flaps 10 of each cropengaging element 1 form extensions of the reclined side surfaces of theprojections. Flaps 10 may be provided, for example, by profiled piecesof flexible sheet plastics material, each of which may be clampedbetween the respective projections providing leading edge 4 and atapered block 31 at the rear. Block 31 may be bolted or otherwisesecured to the projection providing leading edge 4.

The arrangement permits use of thin, sheet-like inserts so that thelaterally protruding wings or flaps 10 are particularly flexible and maybe readily replaced and interchanged. The flexibility may be such thatonly in operation of the apparatus are the wings maintained in theireffective working positions under centrifugal effect and are able toyield rearwards in response to increasing crop pressure and friction.The outer edges 5 of the composite element are curved to ensure smoothlateral sliding of the plant stems into the stripping regions betweenadjacent elements.

FIGS. 15c, 15d and 15e show inserts of alternative shape, each havingtwo holes 35 for positive location on the dowels or pins 36 provided toextend rearwards in the spine-like projections which provide leadingedge 4. Different edge profiles of the crop engaging side regions of thethin inserts may include serrated, smoothly curved, a continuousstraight edge or one which is subdivided by slits 11 or byparallel-sided slots, and feather-edged which comprises small serrationsterminating in short slits.

The individual flaps formed by slitting may yield independently, andthis may allow intrusion of plant stems into the normal profile of theelements so that the stems become enveloped momentarily from the sides.The slits 11 may be provided at different angles, and optionally theymay be replaced by parallel-sided slots or other forms of recesses.

In FIGS. 16a, 16b and 16c are shown respectively a front elevation, aside elevation, partly in section, and a plan view of fin-like cropstripping elements which have as an integral part a base plate 6 forsecuring directly or indirectly to moveable support means 32. Theprominent leading edge 4 may be scalloped or serrated and optionallysharpened to aid intrusion and penetration of matted crop layers wherenecessary.

The outer edges 5 of elements 1 have a pronounced curvature, to promoteparticularly smooth and easy sliding of crop material into the laterallyoffset stripping regions between adjacent elements. Base plate 6 may beslideably inserted into a guide plate 8, which may be attachedreleasably or by welding, bonding or other methods to the moveablesupport means 32.

In FIGS. 17a and 17b is shown respectively in front elevation and planview a section of the development of a cylindrical crop stripping rotorin which the crop stripping elements comprise cones made of resilientplastic material and mounted in successive arrays to cause lateralbending of stems and whiplash of the seed-bearing heads.

In operation each cone-shaped element 1 presents to the crop a wedgeproviding on each side of the crop engaging region curved, laterallycontinuous and progressively reclined surfaces. Absence in the cropengaging side regions of outwardly extending abruptly ending surfacesand abrupt edges formed between planes broadly normal to each other, asare presented by some flat planar elements, reduces the detachment ofnon-seed material, for example when harvesting cereal and pulse crops,and it causes the detachment of wanted plant parts mainly by the effectsof beating rather than scraping.

Incorporated into the base portion of each element 1 may be a threadedbolt, dowel, nut or other means for axial attachment to a transverselyextending channel-section mounting bar 33, which is slideably attachedto the tubular moveable support means 32. Successive transverse arraysof cone-shaped crop engaging elements 1 comb through the crop at lateraland circumferential spacings which allow the seed heads to penetrateinwards towards the base regions of the elements.

The elements 1 shown in full outline comprise the leading array, andthose in broken and chain-dotted outlines represent the second and thirdtransverse arrays respectively. The right-hand element of the leadingarray is shown to be optionally the major leading portion of avertically split cone.

FIG. 17c is a side elevation, partly in section, of the leading array ofcone-shaped crop stripping elements 1 shown in FIG. 17a. The hollowmounting bar 33 is retained in guides 8 and has steep sides of equallength normal to its flat outer surface.

In FIG. 17d the mounting bar 33 is shown to be shaped to inclineelements 1 in the direction of rotation of moveable support means 32.Such inclination can contribute to the minimisation of seed loss anddamage in some crops and conditions. The angle of such inclination,relative to the radius from the axis of rotation of support means 32through the base of the outwardly extending axis of element 1, may be upto 45°, or greater for special purposes.

FIGS. 18a and 18b show respectively a front elevation and a plan view ofcrop stripping elements 1, with annular recesses 16 at the base, securedaxially to a transverse hollow mounting bar 33. By way of example theelements 1 in each transverse array are shown to occupy alternatestations circumferentially, but less than or double the populationdensity shown may be provided.

The arrangement illustrated causes the final stripping of wanted cropparts to take place by the co-operation of the recessed base regions ofelements 1 with the outward facing surfaces of hollow mounting bar 33.

FIG. 18c is a side elevation, partly in section, of the arrangement inFIG. 18a. Hollow mounting bar 33 has leading and trailing side faceswhich converge in the outward direction to impel detached crop parts ineither direction of possible rotation of the elements with minimal riskof loss.

FIGS. 19 to 23 are examples, in side elevation and plan view, ofalternative conical and cylindrical crop stripping elements producingthe effects of a double-bevel wedge. They are particularly suited toseparating seeds from crop, with minimal detachment of MOS, because ofthe said absence in the crop engaging side regions of outwardlyextending abrupt edges and other disruptions or surfacediscontinuations.

FIG. 19 shows a cone with an annular protrusion 19, to agitate the cropand contribute to the stripping of forward-facing areas of crop stems.The base region may be cylindrical and/or waisted.

FIG. 20 shows a cone which is waisted at two levels in such a way thatyielding in any direction can readily occur. The waisting, which formsannular recesses 16, also contributes to the efficient stripping fromforward-facing stem regions. Generally, single or multiple annularrecesses may act as multi-directional hinges or joints in elongateelements. The degree of waisting determines the ease and extent ofdeflection of sections of the elements under excess load conditions. Forsome purposes waisting may be so pronounced that only in operation ofthe apparatus are the elements maintained fully in their intendedattitude by centrifugal effect.

FIG. 21 shows a cylinder, which may be solid or hollow and is preferablytruncated at the outer end to an enclosed angle at the front of up toaround 30°. The length of the element may be varied to suitrequirements, but preferably it may be confined to 6 times, mostpreferably to 2 to 3 times, the maximum diameter. Mounting may bearranged to be radial, reclined or forwardly inclined by up to 45°, ormore for special purposes. Optional waisting to form annular recessesmay be provided. Additionally there may be provided on the outer,preferably slanting surface an oversized oval shoe portion 9, as shownin broken outline, for diverting into favourable paths detached cropparticles which may be sliding along the cylinder. FIG. 21 may alsorepresent a front elevation and plan view of a cylindrical element 1.

FIG. 22 shows a crop stripping element in the form of a cone with anelliptical base which may be mounted so that the major axis is orientedin or transverse to the direction of movement. Predetermined alternativesettings may be provided, preferably by self-locking means, and may beused to adapt the stripping device to different crops and conditions.

FIG. 23 shows a fluted cone with rounded ribs 19. Conveniently,provision may be made for this type and some other discrete cropstripping elements to be mounted so that the elements are self-rotating,to increase their effectiveness and to spread wear evenly. Optionally abearing 38 may be provided in the base of the element to facilitaterotation. Optionally also it may be arranged the the flutes are shapedto be helical to induce rotation.

FIG. 24 is a perspective front elevation, on a reduced scale, of a cropstripping rotor 30 and its crop guide cover 21. Crop engaging elements 1are cone-shaped, helically arranged and secured to hollow mounting bars33 attached to moveable support means 32. Conveniently the cone shape ofelements 1 may be confined to the crop engaging front region, and theinner regions of some or all of the elements may be cylindrical.

Conveniently, the harvesting apparatus described in the foregoing may beused with or without seed separating components. In some instances asclean a seed sample as possible may be demanded, whilst in othersnothing, or only the coarsest non-seed fraction, may need to be removed.

Conveniently, the header shown in FIG. 1 may replace the conventionalheader of a combine-harvester. Optionally, it may be provided simplywith means for conveying the collected material into a container ortrailer.

In the harvesting by stripping of grain crops, such as barley, wheat andoats, much of the flag leaf and the chaff are removed from the plantsincidentally by the stripping device. These botanical fractions, unlikethe straw stems, can have a high nutritional value, equivalent to thehighest quality hay, and collection of the detached MOS before or afterseparation of the grain can be of substantial economic benefit tofarmers who rear ruminant animals.

A practical disadvantage of the MOS associated with harvesting bystripping is its low bulk density. Conveniently therefore stripperheaders may be attached, as the intake device, to forage harvesters, toincrease MOS density by comminution, and to balers or briquettingmachines, for compacting the material into dense large or small packagesrespectively. Passing the harvested material through a choppingmechanism has the added advantage that the chopping rotor dislodges anyunthreshed seeds.

There will now be considered the important dimensions and generalarrangements which are appropriate for the effective operation of theembodiments of the invention. The requirements of different seed cropsmay vary appreciably, depending on seed size, stem thickness, cropmaturity and growth habit.

For dwarf crops having low seed or fruiting bodies the minimum groundclearance under the tip envelope of the seed stripping device may be <25mm, and the effective radius of the stripping rotor preferably may be nogreater than 200 mm. A small tip radius is most readily provided by thevertically or forwardly inclined continuous-belt type strippingapparatus, but in short crops stripping rotors of small diameter alsoperform satisfactorily without wrapping.

For the most commonly grown crops, particularly cereal and pulse crops,the effective length of the crop stripping elements may be preferably40-160 mm, most preferably 50-80 mm. The overall length range of theelements for all types of crop may include 20 and 240 mm. Convenientlythe crop stripping device may have different tip radii as a result ofthe elements extending outwards from the moveable support means fordifferent distances, and transverse and/or circumferential arrays ofcrop stripping elements may comprise different types of element.

Conveniently the effective width of wedge-form crop stripping elementsmay vary between 10 and around 200 mm, preferably between 20 and 80 mm.

Preferably the lateral inclination of the principal plane of the cropengaging surface of wedge-form crop stripping elements in 10° to 65°relative to a radial plane perpendicular to the transverse rotor axis.

Conveniently the maximum effective radius of seed stripping rotors forthe majority of crops in temperate climates may be around 500 mm, andthe maximum effective length of a continuous belt-type seed strippingdevice 1500 mm. The preferred effective radius of a crop stripping rotorfor general purpose use ranges between 200 and 350 mm.

Conveniently the tip speeds of the crop engaging elements on a cropstripping rotor or belt may vary between 8 and 40 m/s, the preferredrange being 12-30 m/s, and the most preferred 15-24 m/s.

I claim:
 1. Apparatus for harvesting crops comprising:a mobile supportstructure for movement over the ground; movable support means extendingtransversely across the direction of forward movement of the apparatus;a plurality of crop engaging elements secured to the movable supportmeans and extending longitudinally outwardly from said support means;means mounting said movable support means for movement, relative to saidsupport structure, such as to cause said crop engaging elements to combthrough a naturally disposed uncut crop into which the movable supportstructure is moved; at least some of said crop engaging elementscomprising crop stripping elements, each having, at least in an outerregion thereof, a form which, in section through the elementsubstantially perpendicular to the direction of longitudinal extent ofthe element, presents the configuration of a wedge pointing in thedirection of movement of the element consequent upon said movement ofthe movable support means whereby the crop stripping element presents anarrow leading edge facing in the direction of movement of the elementduring such movement of the movable support means, and each cropstripping element having reclined side surfaces with outer boundariesshaped to promote smooth sliding and funnelling of crop material intoprincipal inwardly and circumferentially extending crop engagementchannels formed between laterally and circumferentially adjacentelements; means for imparting said movement to the movable supportmeans; and crop containment and guide means extending over or under theapparatus, whereby, in operation as the apparatus is advanced through anaturally disposed uncut crop, and the movable support means is moved bysaid driving means, the crop stripping elements will comb through thecrop to penetrate and split the crop mass apart and to detach andrecover by lateral impelling wanted plant parts, and the cropcontainment and guide means will prevent detached wanted crop parts frombecoming lost and will direct them rearward for collection.
 2. Apparatusaccording to claim 1 in which the wedge effective in the direction ofrotation is of acute wedge form.
 3. Apparatus according to claim 1 inwhich each crop engaging element has side boundaries which convergeinwardly, or first converge and then diverge inwardly, from the distalregion.
 4. Apparatus according to claim 3 in which the crop engagingelements each have an outer wedge shaped shoe, for moving theundisturbed and unsupported crop mass apart, and a stem portion, fordetaching and impelling wanted plant parts.
 5. Apparatus according toclaim 4 in which said stem portion is outwardly flared, tapered orrecessed towards the boundaries of the shoe.
 6. Apparatus according toclaim 1 in which the crop engaging elements are provided with cavitiesto facilitate mounting or to afford favorable yielding characteristics.7. Apparatus according to claim 1 in which at least some of said cropengaging elements are pliable and/or hollow elements which are providedinternally with outwardly extending reinforcing fibers to preventelongation under centrifugal effect.
 8. Apparatus according to claim 1,in which at least some of said crop engaging elements are elongateelements which have one or more regions in which the cross-sectionalarea is reduced to such an extent that in operation of the apparatusthose regions act as multi-directional joints or hinges.
 9. Apparatusaccording to claim 1, in which at least some of said crop engagingelements provide a first spine portion affording a leading edge of thewedge and freely yielding flaps projecting laterally and rearwardly fromthe spine portion.
 10. Apparatus according to claim 1 in which the cropengaging elements are in the general form of perpendicular or obliquecones and cylinders, at least in the crop engaging front regions. 11.Apparatus according to claim 10 in which each crop engaging element hasone or more annular protrusions or recesses to contribute to thestripping effect.
 12. Apparatus according to claim 10 in which the cropengaging elements have cross-sectional shapes which provide a respectivemajor and a minor axis of each element so that either axis may beoriented in or across the direction of rotation, to meet differentrequirements for stripping.
 13. Apparatus according to claim 1 in whicheach crop engaging side and outwardly extending boundary region of acrop stripping element is formed from front to rear of a smoothcontinuous surface, or surfaces, free of outwardly extending abrupt ordefinitive edges and other disruptions or surface discontinuations, todetach plant parts by the effects of beating and avoid the mechanism ofspacing and other edge-induced effects.
 14. Apparatus according to claim1 in which the crop engaging elements are secured indirectly to saidmoveable support means, said elements being secured to hollow or solidtransverse members or bars.
 15. Apparatus according to claim 14 in whichthe crop-facing regions of said transverse members are adapted tocontribute to the crop stripping effect and to the impelling of detachedplant parts towards a collection facility.
 16. Apparatus according toclaim 1 in which crop engaging elements are adapted to rotate inoperation of the apparatus about their outwardly extending axes. 17.Apparatus according to claim 1 in which the moveable support means isdriven to move the crop engaging elements in the overshot or in theundershot mode.
 18. A machine for harvesting seed and forage cropsincorporating as an intake section an apparatus as claimed in claim 1.19. A machine for chopping seed and forage crops incorporating as anintake section an apparatus as claimed in claim
 1. 20. A machine forcompacting field crops and crop residues incorporating as an intakesection an apparatus as claimed in claim
 1. 21. A method of harvesting acrop comprising:providing an apparatus for harvesting crops comprising:a mobile support structure for movement over the ground; movable supportmeans extending transversely across the direction of forward movement ofthe apparatus; a plurality of crop engaging elements secured to themovable support means and extending longitudinally outwardly from saidsupport means; means mounting said movable support means for movement,relative to said support structure, such as to cause said crop engagingelements to comb through a naturally disposed uncut crop into which themovable support structure is moved; at least some of said crop engagingelements comprising crop stripping elements, each having, at least in anouter region thereof, a form which, in section through the elementsubstantially perpendicular to the direction of longitudinal extent ofthe element, presents the configuration of a wedge pointing in thedirection of movement of the element consequent upon said movement ofthe movable support means whereby the crop stripping element presents anarrow leading edge facing in the direction of movement of the elementduring such movement of the movable support means, and each cropstripping element having reclined side surfaces with outer boundariesshaped to promote smooth sliding and funnelling of crop material intoprincipal inwardly and circumferentially extending crop engagementchannels formed between laterally and circumferentially adjacentelements; means for imparting said movement to the movable supportmeans; and crop containment and guide means extending over or under theapparatus, whereby, in operation as the apparatus is advanced through anaturally disposed uncut crop, and the movable support means is moved bysaid driving means, the crop stripping elements will comb through thecrop to penetrate and split the crop mass apart and to detach andrecover wanted plant parts, and the crop containment and guide meanswill prevent detached wanted crop parts from becoming lost and willdirect them rearward for collection; moving through the uncut crop saidapparatus; driving said movable support means so that said crop engagingelements comb through the naturally disposed crop at a front region ofthe apparatus, whereby said crop stripping elements form bevelled wedgeseffective in the direction defined by rotation of the elements aroundthe transverse axis of the support means and movement of the apparatusthrough the crop, to penetrate and split the crop mass apart and todetach wanted parts from the plants; and impelling detached crop partssubstantially laterally and rearwardly towards a collection facility.22. A method according to claim 21 whereby the wanted crop parts aredetached and impelled towards the said collection facility at least inpart by the effects of crop-facing regions of transverse mountingmembers provided on said moveable support means.
 23. A method accordingto claim 21 whereby the wanted crop parts are detached by the effects ofbeating the crop, without scraping it, by using crop stripping elementswhich are devoid in the side regions of outwardly extending abrupt ordefinitive edges and other disruptions or surface discontinuations. 24.A method of harvesting seed and forage crops by using a machinesubstantially as claimed in claim
 19. 25. A method of harvesting fieldcrops and crop residues by using a machine substantially as claimed inclaim 20.